Considering that the existing assessment methods depend on expert’s experience and knowledge excessively, this paper presents an assessment method of SF6 high-voltage circuit breakers based on statistical regularity of samples of breakers. After identifying relations between the experimental and monitoring items and the deterioration properties of breakers, the assessment index system is constructed. The score functions of status items are proposed by analyzing their characteristics. Meanwhile, the weights of status items are calculated by using confidence coefficients of association rules to scale their relative importance quantitatively and objectively. The variable-weight formula is adopted and the equilibrium parameters are selected experimentally to calculate weight coefficients of comprehensive indices, thus to settle the imbalance of comprehensive state relative deterioration degree. The instances illustrate that the proposed method is able to evaluate the comprehensive state of SF6 high-voltage circuit breakers effectively, which provides a new method for safety control and condition maintenance of circuit breakers. This work is supported by National Natural Science Foundation of China (No.71571101).